I had reviewed publication 915 in determining that he had taxable income last year, given the amount of 10+ years benefits. (This was then complicated by having to reimburse the insurance company for disability benefits in excess of what SS paid to my husband's SSN.)

I do not expect that my son will owe anything this year, given the so-called "normalcy" of the income sources this year, and the fact that they are all for "only" a 12-month period. His savings accounts, given the low balance and rates, do not give him any significant income to worry about.

I did not want to encounter any "failure to file" penalties on behalf of my son, if the IRS is anticipating receipt of a return under his name going forward. It sounds like the SSA-1099 alone should not trigger the IRS to expect his return.